Sunburn Solutions

All light-colored horses, and those with white markings, have the potential to develop sunburn when the skin is exposed to light.

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Q:My neighbor/best friend has a major problem with sunburn on her Appaloosa mare. She is basically a black mare with spots on her rump, but not on a true blanket, as such, yet her sunburn is really nasty. It is pink and inflamed, and we have not really been able to find anything that would help it. What do you recommend to help it heal? She is now in a pen that is completely roofed, rather than out on the pasture, but we need to get this healed.

Deby Zimmerman, Boone, Colo.

A:I'm sure everyone has great sympathy for your neighbor's horse since they have probably suffered from sunburn and its consequences! It is typically painful and causes blisters, which then lead to dry and cracked skin with hair loss. All light-colored horses, and those with white markings, have the potential to develop sunburn when the skin is exposed to light. This can include breeds such as Appaloosas, Paints, and Pintos.

Photodynamic agents are responsible for transferring energy from the light into body cells, causing damage. These can include a variety of pharmaceutical agents (such as tetracyclines) and plants (St. John's Wort, buckwheat, and perennial rye-grass). Alfalfa or clover might induce similar symptoms. Plants containing pyrrolizidine alkaloids (ragwort, tarweed, rattle-weed, and salvation jane) might cause photosensitivity in horses with liver disease.

Solutions include decreasing sun exposure (as you have done), especially during the warmest period (noon to 5:00 p.m.). Liberal use of brightly colored, water-resistant sunscreen (SPF of greater than 30) that you will be able to see from a distance whether it has been rubbed off, grooming products that contain sunscreen, a sunscreen-soaked flysheet, and having your local veterinarian perform a good physical examination and perform some blood tests to check for a liver disorder are plausible options.

Have a walk through your pastures and try to identify any offending plant. In consultation with your vet, a course of antibiotics/corticosteroids might assist in reducing the degree of infection and inflammation. Vitamin E gel is great to use on affected areas and might also help soothe them. In the long term, horses that are chronically exposed to harsh sunlight might be at risk for skin cancer, also called squamous cell carcinoma.

I trust that matters will resolve speedily and that your friend will be back in the saddle again soon!